If I use generic array type instead of regular array it panics.

[myyrakle]

Describe the bug To reduce boilerplate, I defined a generic array type instead of using a named type of array.

To Reproduce First of all, I defined the following generic array wrapper:

package slices

type SliceWrapper[T any] []T

func (s SliceWrapper[T]) Append(v T) SliceWrapper[T] {
    return append(s, v)
}

func (s SliceWrapper[T]) IsEmpty() bool {
    return len(s) == 0
}

func (s SliceWrapper[T]) Len() int {
    return len(s)
}

func (s SliceWrapper[T]) First() T {
    if s.IsEmpty() {
        var t T
        return t
    }

    return s[0]
}

Previously, I defined and used the following response dto type.

...
type ShopsResponse []ShopResponse

type ListShopsResponse struct {
    Shops      ShopsResponse      `json:"shops"`      
    Pagination PaginationResponse `json:"pagination"` 
}

But if I apply a generic type like this:

...
type ShopsResponse slices.SliceWrapper[ShopResponse]

type ListShopsResponse struct {
    Shops      ShopsResponse      `json:"shops"`      
    Pagination PaginationResponse `json:"pagination"` 
}

It panics and fails.

2024/02/19 18:28:31 Generating domain.ShopsResponse
panic: interface conversion: ast.Expr is *ast.ArrayType, not *ast.StructType

goroutine 1 [running]:
github.com/swaggo/swag.(*PackagesDefinitions).parametrizeStruct(0x14003b16c18?, 0x140009c06c0, 0x14003b23290, {0x140041bd3e1, 0x21}, 0x30?)
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/generics.go:145 +0xe60
github.com/swaggo/swag.(*PackagesDefinitions).findGenericTypeSpec(0x140000a06c0, {0x140041bd3e1, 0x21}, 0x140009c06c0?, 0x0?)
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/packages.go:435 +0x12c
github.com/swaggo/swag.(*PackagesDefinitions).FindTypeSpec(0x140000a06c0, {0x140041bd3e1, 0x21}, 0x140009c06c0, 0x0)
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/packages.go:392 +0x738
github.com/swaggo/swag.(*Parser).getTypeSchema(0x140001581c0, {0x140041bd3e1, 0x21}, 0x0?, 0x0)
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/parser.go:891 +0x6c0
github.com/swaggo/swag.(*Parser).parseGenericTypeExpr(0x140001581c0, 0x14000166120?, {0x103563550?, 0x14001835920})
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/generics.go:344 +0xf4
github.com/swaggo/swag.(*Parser).parseTypeExpr(0x140001660f0?, 0x1033b61c7?, {0x103563550?, 0x14001835920?}, 0x18?)
        /Users/myyrakle/go/pkg/mod/github.com/swaggo/swag@v1.8.6/parser.go:1192 +0x518

Expected behavior In my opinion, since generics are removed from preprocessing, they should behave the same as they would without generics. But it didn't work that way.

Of course, I know that the principle is different since this is generate before compilation. Is support for these features possible?

Screenshots

Your swag version v1.8.6

Your go version go version go1.20.6 darwin/arm64

Desktop (please complete the following information):

• OS: macOS
• Browser: none
• Version: ventura 13.3

Additional context

[sdghchj]

Try the latest version of swag.

[myyrakle]

Since I use the latest version, there is no panic, but it doesn't generate like an array.

I think this is probably intentional behavior from here on out. We will custom process the rest ourselves.

The issue is closed.